Intraluminal medical devices are commonly used in a variety of medical procedures. For example, stents are commonly used to provide intraluminal support to a body vessel, such as a coronary artery. Minimally invasive techniques are frequently used to delivery such medical devices to a desired point of treatment and to deploy the medical device at the point of treatment. In these techniques, a delivery system is used to carry the intraluminal medical device through a body vessel and to the point of treatment. Once the point of treatment is reached, the intraluminal medical device is deployed from the delivery system, which is subsequently withdrawn from the point of treatment and, ultimately, the body vessel.
Body vessels are typically soft and elastic in nature. As a result, body vessels have a variable cross-sectional shape and frequently change between various cross-sectional configurations depending on various factors, including current body activity and position. For example, veins frequently exhibit a substantially circular cross-sectional shape when the body is ambulatory but exhibit a substantially ovoid cross-sectional shape when the body is in a supine or prone position. As a result, most body vessels are dynamic and can be viewed as having major and minor cross-sectional axes.
Some intraluminal medical devices include a functional mechanism that is sensitive to orientation within a body vessel relative to one or more cross-sectional axes of the body vessel. An intraluminal medical device may include a functional mechanism that may not perform entirely as desired if the functional mechanism is not positioned in a particular orientation relative to one or more of the cross-sectional axes of the body vessel following deployment. For example, some prosthetic valve devices include a valve orifice having a major and a minor axis. For some valve devices, it may be desirable to substantially align the major axis of the valve orifice with the major axis of the vessel when it is in a configuration having a substantially ovoid cross-sectional shape, such as when the patient is in a supine position during the implantation procedure. In some circumstances, the valve device may not function as desired if this alignment is not achieved, particularly if the major axis of the valve orifice is grossly misaligned with the major axis of the body vessel. The leaflets of a valve device that is mis-oriented in this manner may be obstructed or otherwise affected by such orientation. Furthermore, other types of intraluminal medical devices, such as drug-coated stents, may include a functional mechanism, such as a localized deposit of a bioactive, that should be positioned immediately adjacent a particular circumferential portion of a vessel wall, such as a point at which a plaque has developed or has been deposited, to achieve a desired treatment outcome.
Positioning intraluminal medical devices within a body vessel in a manner that achieves such desired orientations relative to the body vessel can be difficult. During conventional percutaneous delivery and deployment procedures, the intraluminal medical device is deployed from a delivery system at a remote location within the body vessel. Monitoring the orientation relative to the body vessel is often difficult with conventional delivery systems, even with sophisticated imaging equipment and techniques, and adjustment of the orientation by rotating a conventional delivery system about a lengthwise axis is an imprecise approach that is viewed by many skilled artisans as difficult to control and ineffective. Prior art delivery systems may not provide a desirable system for deploying such intraluminal medical devices in a manner that achieves the desired orientation. Accordingly, there is a need for improved delivery systems and methods of delivering intraluminal medical devices.